<scp>H</scp>435‐containing immunoglobulin <scp>G</scp>3 allotypes are transported efficiently across the human placenta: implications for alloantibody‐mediated diseases of the newborn

Abstract

We demonstrate that the poor maternal-fetal transport of IgG3 is only true for most individuals of western populations where the G3m16 is not common. In G3m16(+) individuals, expressing H435-containing IgG3, IgG3 transport is similar to IgG1, which may give rise to enhanced complications in pregnancy-associated alloimmune disease in ethnic communities where this naturally occurring H435 containing IgG3 allotype is more frequent.